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<h2><a name="introduction"></a>Introduction</h2>

<p>Lua Object Model (LOM) is a representation of XML elements

through Lua data types. Currently it is not supposed to be 100%

complete, but simple.</p>

<p>LuaExpat's distribution provides an implementation of LOM that

gets an XML documenta (a string) and transforms it to a Lua table.

The only function exported is <strong><code>lxp.lom.parse</code></strong>.</p>

<h2><a name="characteristics"></a>Characteristics</h2>

<p>The model represents each XML element as a Lua table. A LOM

table has three special characteristics:</p>

<ul>

    <li>a special field called <strong><code>tag</code></strong> that holds the

    element's name;</li>

    <li>an optional field called <strong><code>attr</code></strong> that stores

    the element's attributes (see <a href="#attributes">attribute's

    section</a>); and</li>

    <li>the element's children are stored at the <em>array-part</em> of

    the table. A child could be an ordinary string or another XML

    element that will be represented by a Lua table following these

    same rules.</li>

</ul>

<h3><a name="attributes"></a>Attributes</h3>

<p>The special field <strong><code>attr</code></strong> is a Lua table that

stores the XML element's attributes as pairs

<em>&lt;key&gt;=&lt;value&gt;</em>. To assure an order (if

necessary), the sequence of <em>key</em>s could be placed at the

<em>array-part</em> of this same table.</p>

<h2><a name="examples"></a>Examples</h2>

<p>For a simple string like</p>

<pre class="example">

    s = [[<abc a1="A1" a2="A2">inside tag `abc'</abc>]]

</pre>

<p>A call like</p>

<pre class="example">

    tab = lxp.lom.parse (s))

</pre>

<p>Would result in a table equivalent to</p>

<pre class="example">

tab = {

        ["attr"] = {

                [1] = "a1",

                [2] = "a2",

                ["a2"] = "A2",

                ["a1"] = "A1",

        },

        [1] = "inside tag `abc'",

        ["tag"] = "abc",

}

</pre>

<p>Now an example with an element nested inside another element</p>

<pre class="example">

tab = lxp.lom.parse(

[[<qwerty q1="q1" q2="q2">

    <asdf>some text</asdf>

</qwerty>]]

)

</pre>

<p>The result would have been a table equivalent to</p>

<pre class="example">

tab = {

        [1] = "\

        ",

        [2] = {

                ["attr"] = {

                },

                [1] = "some text",

                ["tag"] = "asdf",

        },

        ["attr"] = {

                [1] = "q1",

                [2] = "q2",

                ["q2"] = "q2",

                ["q1"] = "q1",

        },

        [3] = "\

",

        ["tag"] = "qwerty",

}

</pre>

<p>Note that even the <em>new-line</em> and <em>tab</em> characters are stored 

on the table.</p>

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